Device for unscrewing and withdrawing pipe



W. C. THOMAS, l'. C. DICKENS AND I. W. FDWLER.

DEVICE FOR UNSCREWING ND WITHDRAWING PIPE.

APPLICATION FILED FEB. I9, 1921.

Patented Sept. 6, 1921.

UNITED STATES PATENT OFFICE.

WILLIAM C. THOMAS, JAMES C. DICKENS, A N'D JESSE W. `FOWllfElt,

or eoosn 01mm,

TEXAS. l

DEVICE FOR 'UNSCREWING AND WITHDRAWING PIPE.

Specication of Letters Patent.

Patented Sept. 6, 1921.

Application led February 19, 1921. Serial No. 446,495,

T o all whom t may concern."

Be it known that we, WILLIAM C". THOMAS, JAMES C. DICKENS, and JESSE W. FOWLER, citizens of the United States, residing at Goose Creek, in the county of Harris and State of Texas, have invented certain new and useful Improvements in a 'Device'for Unscrewing and Withdrawing Pipe, of which the following is a Specification.

This invention relates to new and useful improvements in a. device for unscrewing and withdrawing pipe.

One object of the invention is to provide a device of the character described specially adapted for use in unscrewing and withdrawing pi'pe from a well bore.v

Another object of the invention is to provide a device of the character which may be operated in either direction and which may be readily brought into engagement with the joints of a pipe, stuck in a well bore, to unscrew and withdraw them singly therefrom.

With the above and other objects in view this inventionvhas particular relation to certain novel features of construction, operation and arrangement of parts, an example of which is given in this specification and illustrated in the accompanying drawings, wherein Figure 1 is a vertical sectional view of the device.

Fig. 2 shows a employed.

Figs. 3 and 4 show plan and side views, respectively, of a bearing block employed.

Fig. 5 shows a perspective viewof an engaging jaw employed, and

Figs. Gland 7 show plan and side views, respectively, of a clutch member employed.

Referring now more particularly to the drawings the numeral 1' refers tothe drive stem which 'works through the stuffing boxes 2 and 3, the former of which is located in the upper end of the tubular nipple 4. and the latter of which is located in the lower end of the tubular nipple 5. The nipple 4 is connected to the lower end of the pipe 6 by means of the collar 7 and the nipple 5 is connected, by left hand threads, to the plan view of the gearing depending neck 8 of the internal spur geary flange 11 on which the internal annular shoulder 12 of the coupling rests. The lower end of this coupling is screwed, with left hand threads, onto the tubular section 13 which carries a fishing tool, (not shown) of any conventional form. Underneath the neck 8 there is a collar 14 fastened on the nipple 5 and there is a coil spring 15 which surrounds said nipple and is interposed between the collar 14 and the coupling 10. Above this coupling there is a key 16, carried by said nipple, which is adapted to move into a keyway17 of the coupling 10 when the nipple moves downwardly through the cou- The internal gear 9 works in the bearing 18 whose lower end is formed with a retaining fiange 19 whereon said gear rests and the lower end of the anchor block 20 is reduced and threaded into the upper end of the bearing 18. The upper end of the anchor block has a deep recess 2l and threaded onto t'he reduced upper'end of said block there is a tubular casing 22 whose upper end is closed by-means of a gland 23 which surrounds the nipple 4 and is threaded into said casing. This gland is formed with internal spaced projections 24 adapted to, at times, mesh with similar projections 25 carried by the nipple 4 to form a clutch. i

The lower end of the nipple 4 has an annular shoulder 26 ^and the upper end of the possible and it has the upper and lower in.

ternal annular flanges 30, 31, the former of which engages over the shoulder 26 and the latter of which fits into the groove 28. The block 27 fits into the recess 21 and has a plurality of vertical dovetailed peripheral grooves 32 in which the dovetailed jaws 33 are adapted to slide. These jaws vwork through alined slots 34 cut through the walls of the recess 21, and engage with the well casing 38. v

Splined on the stem l there is a spur gear 35 which is in mesh with a plurality of similar gears 36 whose shafts have upper bearings in the lower end of the anchor block 20 and lower bearings in the bearing plate 37. The gears 36 are in mesh with the internal gear 9 and when the stem is rotated the gear9 and the nipple 5 carried thereby wili rotate in the reverse direction.

rl`he device is assembled as shown in Fig. l and let down into the well bore until the fishing tool contacts with the pipe to be pulled. The spring l5 will be compressed by the weight sustained by it, thus minimizing the shock. The downward movement of the pipe section 13 and coupling 10 being arrestedl the key 16 will move into the keyway 17 and said coupling and pipe section 13 will be 'forced to rotate with the nipple 5. lf the stem l is rotated forwardly, that is, in a clockwise direction, the pipe section 13, and the fishing tool carried thereby, will rotate in the opposite direction. This fishing tool used in unscrewing the joints of the pipe to be withdrawn is usually a conical.

shaped tap having left hand threads and as it is so rotated it will screw into the upper end of the' pipe section to be unscrewed and engage therewith and unscrew the same and it may be then withdrawn. While unscrewing the pipe the anchor block 20 and its appendants are held stationary by the jaws 33.

lf it is desired to rotate the fishing tool forwardly, for any purpose, as for example to disengage it from the pipe to be pulled, the pipe 6 may be pulled upwardly to bring the -projections 24 and 25 into clutching po. sition. This upward pull on the pipe 6 will cause the corresponding elevation of the block 27, the jaws 33 moving downwardly and inwardly, to release the casing, and the entire device may then be rotated forwardly with the result sought to be obtained, as above specified,'or withdrawn from the bore.

What we claim is 1. A device of the character described, including a driving member, a driven member, an anchor, means carried by the anchor whereby the device is fixed in a well casing, means carried by the anchor and operatively connected with the driving member and the driven member, through which the rotation of the driving member will be imparted, in a reverse direction, to the driven member, a tubular member depending from the driven member and arranged to be clutched therewith and declutched therefrom.

2. A device of the character described, in-

cluding a driving member, a driven member,

an anchor, means carried by the anchor nasa'ie whereby the device is 'ir-ined in a weii casing, means carried by the anchor and operatively connected with the driving member and the driven member, through which the rotation of the driving member will be imparted, in a reverse direction, to the driven member, a tubular member depending from the driven member and arranged to be clutched therewith and declutched therefrom, and a yieldable cushion interposed between said driven and tubular members.

3. In a device of the character described, an anchor for. securing the device against rotation in a well casing, said anchor consisting of an anchor block, a bearing block movable vertically relative thereto, jaws carried by said bearing block and normally in engagement with said casing, a driving member working through said blocks, a driven member depending from and rotatable relative to said anchor block and gearing operatively connecting the driving and driven members, through which the rotation of the driving member is imparted to the driven member in the opposite direction.

4. In a device of the lcharacter described, an anchor block having a recess formed therein with slotted walls, a bearing block in said recess, jaws slidably connected to said bearing block and normally working through said slots into engagement with a well casing, said slidable connection being formed to withdraw the jaws from the casing when the bearing block is elevated, means for elevating the bearing block, a driving member working through said blocks, a driven member depending from and rotatable relative to the anchor block, an operative connection between said members, whereby the rotation of the former is imparted in a reverse direction to the latter, and a clutch for connecting said elevating means, wheny elevated, with said anchor block to prevent their independent rotation.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

wiLLIAM o. THOMAS. JAMES o. DioKENs. JEssE w. ro-wLEn.

Witnesses:

R. M. SMITH, Wir. A. CATHEY. 

